The long-term goal of this research is to find a more effective medical and pharmacological management of ureteral calculus disease. Ureteral activity and urine output will be studied in an acute animal experiment and response to variations in urine flow rate, drugs and surrogate calculi will be determined. Methods of assessing ureteral activity in the acute model will include the use of small optical sensors and the recording of activity on cine film which will later be digitized and analyzed and a three-dimensional plot constructed. A series of chronic animal experiments employing sub-human primates will test the effect of edema and fibrosis of the ureteral wall and the effect of fluid intake, posture, activity, anti-inflammatory and other drugs on the passage of surrogate calculi. Chronically implanted optical sensors will monitor ureteral activity and be linked to a recorder via a backpack telemetry system. Finally, clinical trials of the drugs and factors found to be important in the animal models will be undertaken.